ConcurrentUtils.jl provides high-level and low-level programming tools for concurrent computing in Julia in order to complement the Base.Threads library. The high-level APIs include:

• Promise{T}: a memory location that holds a value of type T that can be set once and retrieved asynchronously.
• @tasklet code: a Promise-like memoized thunk.
• @once code: execute the code at most once.
• ReadWriteLock: a reader-writer lock.
• ... and more

See more in the Documentation.